Sheet-metal-bending machine and method of treating the same



F. GOELER Fkb.24.l925.

sEEET METAL SEEDING MACHINE AND METHOD 0E TREATING THE SAME v F. GOELERSHEET METAL BENDING mam AND METHOD oF mamme :um sms' Filed Aug. 25, 192;

2 Sheets-Sheet 2 Patented lid, i925.

UNITED STATESPA-TENT OFFICE.

FREDERICK GOELER, OF ALAMEDA, C tLIFOIR-NIA, `A'SIf-HRTOR T EMMA. A.GOELER,

, OF ALAMEDA, CALIFORNIA.

SHEETMETAL-BENDING MACHINE AND METHOD O'F TREATING THE SAME.

Application filed. August 25, 1921. Serial No. 495,375.

l To @ZZ 'whom 'it may concern;

Be it known that lf, FREDERICK Gontran,

a citizen of the United States, residing at Alameda, in the county ofAalameda and Fitate of California, have invented new and usefulimprovements in Sheet-itietal-Bending Machines and Methods of Treatingthe Same, of which the following is a specification.'

This invention relates to improvements in sheet metal bending machinesof the type described in Letters Patent of the United States, Nos.1,131,055 and 1,162,050, granted to me March 9, 1915 and November 30,1915, respectively.

Illhe invention has particular' reference to improvements in the bendingmembers or jaws of the machines of the character described and theprimary object is to prohave maximum strength and durability and not besubject to disruption or warping or bending during the bendingoperation.

ln bending machines of the character described in the patents abovementioned, the bending jaw or plate is relatively long and is hinged orpivoted at its ends to a frame, whereby relatively wide or long piece ofsheet metal to be bent may be inserted between the hinges or pivots. inmachines of this type it is not possible to use any other means ofconnection between the bending plate or jaw and the frame other than themeans at the ends of the plate and for this reason, the jaw plate is aptto warp or bend or buckle intermediate of its ends and when this occursa defective bend in the sheet metal is produced and in some instancesthe bending operation is prevented entirely.

The particular object of the present invention is to provide a method offorming and strengthening or reinforcing a bending plate or jaw of anovel structure, so that the plate or j aw will not be subject towarping or becoming disrupted when in use. The invention also includesmeans for correcting any disruption or warping in the plate, should thesame occur to a slight degree, after the plate is fixed to the machine.

rlhe invention possesses other features and advantages some of which,with the foregoing will be set forth at length in the followingdescription where l shall outline vide a bending member or jaw whichwillv in full that form of the invention which l have selected forillustration in the drawings accompanying and forming a part of thepresent specification. In said drawings lf have shown one form of theconstruction of my invention, but it is to be understood that l do notlimit myself to such form since the invention as expressed in the claimsmay be embodied in a plurality of forms.

Referring to the drawings:

Figure l is a front elevation of a sheet metal bending machineconstructed in accordance with the present invention.

Fig. 2 is an enlarged rear elevation of the bending jaw or plate formingthe particular part of this invention.

Fig. 3 is a vertical sectional view? taken on line 3-8 of Fig. 2.

Fig. 4 is an enlarged fragmentary sectional view of the bending plate orjaw and the work holding or clamping means with which it'cooperates,showing a piece of sheet. metal to be bentin position for bending, indotted lines and the manner of use of the angle bar on the bendingmember.

Fig. 5 is a fragmentary perspective view of the bending plate or jawshowing the slide member used during the process or method ofstrengthening the plate or aw.

Fig. 6 is an edge elevation of the plate or jaw showing the same as itwould appear when being treated to reinforcing and strengthening thesame.

ln carrying out the present invention an elongated steel plate ofsubstantially rectilinear outline is reinforced by riveting upon theback thereof near to its upper edge a T bar. Aafter this reinforcingelement is secured to the back of the plate, the plate is placed upon asuitable work table or supported upon a bar or mandrel and pressure isapplied by any suitable means to the ends of the plate so as to causethe plate to assume an arcuate form due to the position of the mandrelupon which the plate rests. The plate is held in this arcuate or bentshape by any suitable means and is next treated so that it will, uponremoval of said holding means, maintain a curved or arcuate shape. Inorder to cause the plate to have a permanent bend or curve, I preferablyplace upon the one side of the angle of the T bar, a solid,comparatively heavy metal block or rail and then with the sledge orother suitableheavy instrument, strike the vertical member of the T barthroughout the length thereof, at intervals, so as to stretch the metalof the bar. By striking the T bar, preferably with asharp pointed heavyinstrument, the metal is stretched so that when pressure is releasedfrom the ends of the plate, the plate will have a permanent curve orarcuate form. A straightening or adjusting means is attached to theplate and before the bending operation is preferably in the form oit arigid V-shaped bar or rod secured at its ends to the end portions of theplate with the apex otl the V disposed below the lower edge andcentrally of the ends ot the plate. An adjusting bolt with a nut isadjustably secured to the lower edge of the plate and when operatedexerts a pressure upon the V rod such that the plate will tend tostraighten out. To make the plate suitable for use, the adjusting meansisoperated so that a strain is placed upon the ends oft the plate suchas will cause the plate to .straighten out. Vhen the .plate is straightand presents a tlat outer or bending tace, it is then attached to themachine and is ready for use. 'Due to the treatment atoren'ientioned,the plate is under such tension that it possesses maximum inherentstrength and rigidity such as will withstand severe bending strains andwill not vbe subject to buckling or bending.

Referring to the drawings, 1 designates a preferably horizontal table orsupporting structure mounted upon suitable legs 2 and supporting workholding means which comprises jaws 3 and 4 which latter are llocated oneabove the other in a horizontal plane so as to leave a space for theaccommodation ot pieces ot sheet metal to be bent, as shown at 5 in Fig.4. In connection with the table and work holding rmeans including thejaws 3 and 4, there are provided suitable bracing and securing devices 6and means ot adjustment 7 tor the jaws. This means is -fully describedin Letters Patent hereinbetore referred to and need not be described indetail.

Mounted upon the table 1 is a vbending jaw or plate 3 o-t substantiallyrectilinear outline and which normally depends from a pointsubstantially level with the jaw 4. The plate 8 is pivoted or hinged bysuitable means as at 9 at its upper end edges to the table 1 with itsinner side close to the torward edge of the jaw 4 and its upper edgeflush with the upper surface of said jaw, as shown particularly in F ig.4. Suitable means 10 is provided for swinging the plate on its pivots orhinges so as to cause bending of the sheet metal plate 5.

The plate or jaw 8 is constructed of Ihigh grade steel and upon 'itsrear tace adjacent its upper ledge there is riveted a straightreinforcing element 11, preferably in the form of a T bar, the ends ofwhich terminate a few inches short of the ends ot the plate.

To provide for reinforcing the plate tor heavy bending, the outer tacethereof adjacent its upper edge is provided with a longitudinalcountersink 0r recess 12 in which is removably mounted a flat plate 13,as shown in Figs. 3 and 4. The outer tace ot this plate is substantiallyflush with the outer :tace of the plate 8 and the upper edge of theplate is flush with the upper edge ot the plate 8. To further strengthenthe jaw an angle bar 14 maybe removably screwed to plate 13 with theouter t'ace ot one angular portion 15 disposed flush with the outeredges ot the plates 8 and 13, as shown in Fig, 4. lBolts 16 are passedthru the angle bar and plate 13 so as to removably secure these partstogether and similar bolts 1G pass thru the `bar 14, plates 13 and 8, toremovably secure the bar and plate to the jaw. Thus, it will be seen,that in bending heavy sheet metal plate, the upper surface ot the anglebar portion 15 and upper edges of the plates 13 and 8 bear directly uponthe sheet metal to be bent. rllhe angle bar 14 provides a relativelylarge surface to engage the plate to be bent and in this way preventslocalization ot the strains and stresses upon the lbending plate 8. Incertain kinds ol bending work, the bar 14 and plate 13 must be removedand this leaves only the narrow edge of lthe plate 8 .exposed forengagement with the work. Also in some instances it is only desirable toremove the angle bar and utilize the upper edges o'l the plates 13 and 8to bear upon the work. l-.Vhen both the bar 14 and plate 13 are removed,the comparatively narrow edge ot the plate 8 would be subject to bendingor buckling under severe strains, were it not for the treatment oi theplate as hereinbetore described, to prevent this buckling and tbendingtendency. Also when onlyv the bar 14 is removed and the plates 13 and Sare brought into use, the tendency ot the plate 3 to buckle or bend ispresent and the treatment o't' the plate to give it natural inherentstrength prevents the buckling or bending thereof. Thus, it will beseen, it is not mainly when the elements 13 and 14, or particularly theelement 14, is removed 'from the bending plate, that the necessity othaving a plate ltreated with vthe method hereinbeiore described, becomesapparent.

As a means for correcting the alinement of the plate 8 and for placingthe same under such tension that it will have maximum strength anddurability, I employ a heavy substantially V-shaped vbar 17 the ends ofwhich are flattened as at 18 and riveted as at 19 to the end portionsot' the plate S.

.lhe apex of the V bar is disposed centrally of the ends of the plateand beneath the lower edge thereof, as shown in Figs. 1,2 and 3. A bolt2O is vertically adjustably mounted in a keeper member 21 riveted as at22 to the rear face of the plate 8 centrally of the ends of the plateand near the lower edge thereof. The head of the bolt is slotted as at20 and receives the apex portion of the V bar 17, in the slot. l nut 23adjustable upon the eye bolt with its upper face bearing upon the member21. By turning the nut 23 so as to extend the bolt downwardly a strainwill be placed upon the plate 8 such as will tend to correct anycurvatures thereof.

As shown in Figs. and 6, the plate or bending jaw 8 is treated so as tohave maximum inherent strength and durability. After `the flange of thewl" bar is secured to the rear face of the plate, the plate is placedwith the rear side uppermost so that the central portion thereof willrest upon a bar or mandrel 25. Vlihe bar or mandrel is supported upon awork bench or other support. Pressure is applied by any suitable means,not shown, to the end portions of the plate so that the entire plate isbent into a curved or arcuate form, as shown in Fig. (l. rlhe plate isheld in this bent position by the means referred to and while thus helda block or bar of solid metal, shown at 26 in Fig. is placed upon thereinforcing element 11 so as to bear against the vertical or upstandingportion of said element. The vertical portion is then struck a series ofsharp blows with a heavy sharp edged hammer or sledge, (not shown), uponthe face thereof opposite that engaged by the member 26. This strikingof the vertical portion is effected at slightly spaced points throughoutthe length thereof and for such a time that the metal of the member 11will be strctclmd and the plate will have a permanent bend or arcuateform. After hammering of the member 11 the desired extent, the pressuremeans is removed from the ends of the plate and the plate has apermanentl bend longitudinally. The straightening of the plate isaccomplished by adjusting the nut 23 so that the bolt 20 will produce apull upon the t". bar 17. rlhe V bar 17 when thus acted upon causes theplate to straighten and when the plate is thus straightened it is un.-der such tension that it is better able to withstand strains during thebending operation of the machine and not apt to become warped or tobuckle.

1n the operation of the bending machine, the piece of sheet metal, asshown at 5 in Fig. 1l, is placed between the jaws 3 and a so as toengage the angle iron 141 and plate 13, or when the bolts thru the baror plate 13 are removed, will engage the plate 8, and the mechanism isthen operated to swing the plate upwardly. Upon movement of the platethe` bending` of the sheet metal will take place at the point where theouter ed ges of the jaws 3 and l and inner edge of the plate 8 arelocated. 1t is apparent that vari? in use.

l claim:

l. 1n a sheet bending apparatus, means for holding material to be bent,a bending plate arranged so as to be moved in engagement with thematerial to be bent to effect the bending of the material, said bendingplate having a permanent curve in one direction and means on said platefor straighteningv the same so as to place said plate under tension.

2. The method of treating the bending member of a sheet metal bendingmachine, which bending member comprises a relatively long metal plate,which consists in bending said plate so as to produce a permanent.longitudinal curvature therein and then straightening the said plate toremove the longitudinal curvature so as to place the plate undertension.

i3. The method of treating the bending plate of a sheet metal bendingmachine so as to render the same highly resistant against bendingstrains, which consists in securing a reinforcing element tol one sideof the plate, producing a permanent curvature longitudinally in theplate and reinforcing element and then straightening said plate toremove the curvature thereof.

et. The method of treating a bending plate or member of a sheet metalbending machine so as to render the same highly resistant to bendingstrains, which consists in mounting a reinforcing element on the plateso as to cause the plate and reinforcing element to maintain a givenbend or curve then straightening said plate and reinforcing element.

5. 1n a sheet metal bending machine, a frame, means on the frame forholding sheet metal in position to be bent, a bending plate attached atits ends to the frame so as to move with relation to the holding means,means for moving said plate while the same is engaged with the materialto be bent, such. plate having a normal tendency to curve longitudinallyand means carried by the plate for correcting a longitudinal curvaturethereof and for maintaining the plate in straight form.

6. In a sheet metal bending machine, a frame, means on the frame forholding sheet metal in position to be bent, av bending` plate attachedto the frame so that it may be moved in engagement With material to bebent, means for moving' said plate to eli'ect bending el the sheetmetal, said plate having' a normal tendency to curve or bend lon-`e'itndinallj,v and means carried by the plate `tor roriectinp; saidtendency and maintainine the plate in straight forni.

T. In sheet `metal bending` machine, a traine, means on the traine forholding' sheet metal in position to be bent7 a bending plate attached tothe traine so that it may be moved in engagement ywith material to bebent, means ter moving said plate to effect bending et' the sheet metal,said plate having a normal tendency to curve o1' bend longitudinally andmeans carried by the plate tor correcting said tendency and maintain-'fig the plate in straight fori/n, which means comprises a inni securedat 'its end to end portions of the plate and having a mid poi'- tiondisposed below the lower edge of the plate, means carried by the centralportion ot the plate ter transmittingv a torce to said bar snch as Willtend to straighten the plate and remove any curvature thei'eo't'.

FREDERICK GtHLElI.

